44 AutoMag This pistol has very small grip for a magnum autoloader and in fact is smaller in circumference than a Glock 17 9mm. It is very well made and caliber conversions require only a barrel swap to go between the 44AMP, 41 JMP, 357 AMP, 30 LMP, etc. This gun has the best design to facilitate caliber swaps since the sights remain on the barrels, hence there is no need to resight the gun after going to a different barrel. Sights are very nice, as is the trigger and overall handling characteristics of the pistol. This is the easiest of the magnum autos to hit long range targets off-hand. Though the DE is more accurate off the bench, the AutoMag is more accurate when the operator must hand hold the piece. This is mostly due to the superb trigger and better grip ergonomics than the DE. Drawbacks to the AutoMag are that it is not easily scoped and since the barrel moves back and forth during cycling it tends to break scopes in the heavier calibers. Obviously, ammunition is a problem if you do not reload, but if you are a reloader, 44 AMP brass is now available from Starline. Also, all of the necked down calibers use a thick neck, so there is no need to inside neck ream when forming the cases, even down to the 30 LMP. Reliability of the AutoMag is good, but not perfect. Mine tends to have an ejection failure approximately 1 in 150 rounds or so. I have shot a couple of hogs with this gun, one at 55 yards with a 6.5" 41 JMP barrel and one at 85 yards with a 8.5" 41 AMP barrel, both iron sighted off-hand. This is a very nice gun and if you are an experimenter, hand loader, and basic gun nut, this is the magnum pistol for you. If you want to buy off the shelf ammo and shoot your gun all day every day, this is not a good choice since the gun does require more maintenance than others.

And in light of this and the previous post, evidently barrels were available in .357 AMP, .41 JMP, and .30 LMP.